Re: [PATCH] pps: add an error check in parport_attach

[Ma Ke <make24@iscas.ac.cn>]

Greg KH<gregkh@linuxfoundation.org> wrote:
> On Tue, Aug 13, 2024 at 11:08:00AM +0800, Ma Ke wrote:
> > In parport_attach, the return value of ida_alloc is unchecked, witch leads
> > to the use of an invalid index value.
> > 
> > To address this issue, index should be checked. When the index value is
> > abnormal, the device should be freed.
> > 
> > Found by code review, compile tested only.
> > 
> > Cc: stable@vger.kernel.org
> > Fixes: 55dbc5b5174d ("pps: remove usage of the deprecated ida_simple_xx() API")
> > Signed-off-by: Ma Ke <make24@iscas.ac.cn>
> > ---
> >  drivers/pps/clients/pps_parport.c | 10 ++++++++--
> >  1 file changed, 8 insertions(+), 2 deletions(-)
> > 
> > diff --git a/drivers/pps/clients/pps_parport.c b/drivers/pps/clients/pps_parport.c
> > index 63d03a0df5cc..9ab7f6961e42 100644
> > --- a/drivers/pps/clients/pps_parport.c
> > +++ b/drivers/pps/clients/pps_parport.c
> > @@ -149,6 +149,11 @@ static void parport_attach(struct parport *port)
> >  	}
> >  
> >  	index = ida_alloc(&pps_client_index, GFP_KERNEL);
> > +	if (index < 0) {
> > +		pr_err("failed to get index\n");
> 
> No need to be noisy, right?
> 
> thanks,
> 
> greg k-h

Firstly, I would like to express my gratitude for your valuable suggestions
on the patch I submitted. Based on your feedback, I understand that it is 
unnecessary to output error messages in this function. If this 
interpretation is correct, I will make the necessary modifications and 
resubmit the patch v2. Thank you for your response.

Best regards,

Ma Ke